A square is a special case of a parallelogram, rectangle and a rhombus - they all have 2 pairs of parallel sides. A trapezoid cannot be classified as a square because it only has one pair of parallel sides
1) A parallelogram has 2 pairs parallel sides. A square has 2 pairs of parallel sides, so a square is a parallelogram. 2)A rhombus is a parallelogram that have all sides are congruent, a square has all sides are congruent, and as we saw in 1) square are parallelogram. So, a square is a rhombus. 3) A rectangle is a parallelogram that has all angles = 90⁰. A square is a parallelogram ( from 1) and all its angles is 90 degrees, so a square is a rectangle. 4) A trapezoid has only one pair of parallel sides, so trapezoid is not a parallelogram, and square is not a trapezoid.
